STRING 1) – Select which database: Select the first database select 12)–Move key from data 1 to database 0: select 1 move mykey 03)–Set key-value pairs: set myKey abcSet multiple key-value pairs at one time: MSET fruit “apple” drink “beer” food “cookies”4)–Retrieve key-value pairs: get myKey–Get a key randomly: randomkey– View all keys in the database: keys *5)–Delete key: del myKeyNote: If the ke... »
Article directory The following two tables are explainedSELECTDISTINCTWHEREAND ORINBETWEENwildcardLIkeORDER BYfunctioncity tableString functionsCommonly used function examples:concatsubstrtrimregionreplacegroup byhaving Aliassubqueryexiststable linkUse subqueries to implement multi-table queriescreate viewunion intersection valueNo intersection valuecaseThe difference between null and no value (... »
1. Download mysql8.0.26 (currently the latest version) https://dev.mysql.com/downloads/mysql/ 2. No login, just download 3. Unzip the compressed package to the directory where you usually install the software. 4. Configure environment variables after decompression [This computer]-[Right-click]-[Properties]-[Advanced system settings]-[Environment variables]-[Find the path in the system variables]-[... »
I. Introduction As an employee of an e-commerce company, I deeply understand the severe challenges of ensuring the normal use of services under heavy system pressure and high concurrency. During Double 11, our database service was severely strained due to the surge in usage, and the pressure was extremely high. There were even failures such as missed transactions and dirty data. Even if we have a ... »
Today I will continue to introduce you to MySQL-related knowledge. The main content of this article is the basic principles of MySQL Cluster. 1. MySQL Cluster Principle MySQL Cluster is a common technology for MySQL clusters and is suitable for high redundancy and practical versions in distributed computing environments. In MySQL Cluster, the structure and function of the database are split into t... »
1. Background The leader asked to use kettle,Synchronize sqlsever data to mysql, so I thought that the kettle tool can also configure incremental synchronization and scheduled synchronization. As a result, the connection took a long time. I am a newbie and not very familiar with the operation. Hahaha, don’t be dissatisfied, masters, just record the process. Don’t mind your level when writing an ar... »
Guest | Organized by Yu Jun |Nishikari xs Listing |cloud native In the wave of digital transformation, more and more companies are beginning to embrace digitalization to improve work efficiency and reduce operating costs. While digitization helps companies achieve “increase in revenue and reduce expenditures,” the operating costs brought about by digitization itself also deserve attent... »
Article directory Table of contents Preface 1. Three methods to start the SQL server service 1. Impact of not starting the SQL server service 2. Method 1: Use cmd to start the SQL server service 3. Method 2: Use SQL Server Configuration Manager to start the SQL server service 4. Method 3: Start the SQL server service in the service manager 2. Method of establishing database 3. Method of creating t... »
The connection to the database suddenly failed. I searched online for a solution but couldn’t figure out what the problem was. Finally, I found the problem in the Windows log (as a reminder, if there are any strange software errors later, you can check it in Computer Management->System Tools->Event Viewer->Windows Log->Applications) It turns out that the evaluation period is over... »
Mall cluster construction Article directory Mall cluster constructionEnvironment introduction:Build basic environment preparationBuild vsftpd serviceBuild a read-write separated database clusterBuild a Zookeeper service clusterBuild a Kafka service clusterInstall redis serviceInstall Nginx serviceBackend Jar package deploymentAnalysis of Jar package # Approximate service deployment location: # By ... »
